Dog-operating mechanism and knee cushion for sawmill carriages



Febjzl, 1928.

J. M. BROPHY DOG OPERATING MECHANISM AND KNEE CUSHION FOR SAWMILL CARRIAGES Filed Jan. 23. 1926 4 Sheets-Sheet l Feb. 21, 1928. 1,660,118.

J. M. BROPHY DOG OPERATING MECHANISM AND KNEE CUSHION FOR SAWMILL CARRIAGES N Filed Jan. 25. 1926 4 Sheets-Sheet 2 Peb. 21, 1928. 1,660,118

I J. M. BROPHY DOG OPERATING MECHANISM AND KNEE CUSHION -FOR SAWMILL CARRIAGES Filed Jan.23. 1926 4 Sheets-Sheet 3 Feb. 21, 1928. 1,660,118

J. M. BROPHY DOG OPERATING MECHANISM AND KNEE CUSHION FOR SAWMILL CARRIAGES Filed Jan.23. 1926 4 Sheets-Sheet 4 1f/'19* 0" E ZZ 20 3026 52 Z9 .55 1 f -"l 'v n wwf CII Patented Feb. 21, 1928.

JAMES M. BRPI-IY, OF HATTIESBURG, `MISSISSIPPL DOG-OPERATING'YMCHANISM"AND KNEE'CUSHIONOR SAWMILL CARRLAG'EIE.4

.Applicationl file d 'Ianuaryf 23;V 192615 .i Serial No;Y 83,247.

My Iinvention relates to saw-mill.carriages .A :uuhniore particularly', tomeans oroper-q ating the grab `or boss 4dogsV` which. arecar'f ried bythe saW-millkneesand tov means;

ttor cushioning the knees.

ln respect to the dogoperatingfinechanisin, one of theiobjects of theinventionis to providewan improved motive. tluldlioperiatedniechanlsm ,embodying a pistonA and 1a.

cylinderand a novel controlling valve Where?- released or retracted rommthe. logl bythe actionwof any .suitable motive fluid pressure:

master valve' tothe end-that the grabA .dogs4 of any kneemaybe operated independently simultaneously operatedand at any desired motive fluid pressure.

ln practical operation, the dog operating mechanism ot my invention, While. selectively controlled at the will: ofthe; operator. as betweenthe dogs or" the diierent kneeswof the saw-mill, neverthelessfresults in ia full strokeprojection oroperation ofthe grab or boss dogs which the setter elects to operate. The mechanism provides independent manually operated valves Whichcontrol the operation of the dog. operatingl mechanisms o the diiierent knees. n .I Y

H the setter decides that theA logV requires the'operation of only the grab dogs'on .cerf tain knees, he sets the control'valvesonly for those knees. y

llVhen he operates the master valve, the motive iluidpressure, air tor' instance, derived 'from a suitable source,l reducedby a reducing valve tothe pressure desired" or which is best suited to the timberbeing handled bythe mill, immediately khas access to the automatic valves Which control theipisL tons and cylindersv of the knees which are selected, and the dogs et those kneesthen op'- crate. On exhaustingl the air pressure by turningthe individual control valves 4to 4the the grab or boss dogs 'are held normally-A exhfaustwpositiorr, thenormal. air,y pressure to which-,the valves ofthe mechanismsare subject, immediatelyzz-causessrestoration; of the pistons thereoitto `normal position and this', results` iniJ release or. retraction y of the. grabdogs of said knees. Eurthermore-,the settefr'zcanvl instantly .project or. retract` the grabs dogss of anynkneer, Without disturbing the, re-lease'dxorf` projected condition. of theA grabv a dogs of rother knees,.and. thus; dog lthe log asj-hef-maycindtnecessary@1 n `Myl improvements? in the. dog opera-ting mechanismlresultsf in :simplicity of 1 construction,1 ease-#fof'instadlation,economy of operation, as.'-.the-air1 pressure. required need be onlysuflicientzto ifllithe cylinder'forth'e dogs which: have -been:selected,s inasmuch as the pressureA begins;l ande ends ati the. improved automatic. slidesvalve of. the selected cylindergfcy Y There Iis annnimumofipipiirg of'air llines required; `Which-5conserves the air` pressure. and ;causesthe,valves to operate quickly.y

The control i'valvesiz: for the` dog operatingmeans of the respectivekneesandathe masterwzvalve of ,myl invention are ordinary threeawayxvalves Whose;usefisireadilyiunderstoodibyyanyf` practical saw mill man'. f

A The pistons.'andccylinders aref =0` ordinary constri'iction,A bute arezvvprovidedi with my im'- proved vautomatic. .control lvalves. 'These can be readily installed,v be economically]main-v tainediiand.` are; of such'v :simple constructionV that any .practica-l sawvmill.im-an: can Aunder'- standfthemf;

Onlyiafsmall amountof space-is required for the installations of the 'operators lcontrolling valves andastheyy can f'be placed in front' of him, Ihe is never requiredltoI turn his h'eadto operatevthervalves andfthereby possiblyvnriss si-gnalss. given 'to hhnby the Sawyer:V Furthermorafthe ,controls do not interferev'withxthe*quick departure of the setter in 1 casca orf accident; "as -When l the savv lbreakslor the.`v carriage becomes unmanageable. The; pressure 4*reducinggr valve which constitutes :afparti'offmy `invention affords a mea-nsf;Wherebythe am pressure Which'iis power.

W hen small logsare being sawed, the pressure can be reduced correspondingly which be reduced to much less than (when hard timber is being handled by the mill, thereby holding the timber up to a higher average grade than is possible with air-operated dogging devices which, dueto their construction and mode of control and operation, must cause the dogs to penetrate the timber to a certain depth before they dogging action finishes its stroke.

The common practice heretofore has-been to provide springs to cushion the kneesto take care vof the shock towhich they are subject by the impact of the logs. Such cushioning hasnot been adequate for the purpose as it has been found in practice that the cushioning effect needed varies with the size of the log and, for the furtherv reason, because the steam log turnersand impact of the iogs results in slack and wear of the set works and shearing or loosening of the keys which secure the pinions on vthe set shaft. In fact, the hand levers which are commonly used in the setworks become dangerous because their. latchesare liable to givev way. Obviously, a cushion which is set to take care of the shock incident to handling a large log, will be toostiff to properly cushion a smaller log, and vice versa.

My improved knee cushion comprises a piston and cylinder with a linkage connected to the rack of said knee, a manually controlled valve and pipe line leading to each of thev cylinders for the cushions of the different knees, and a pressure reducing valve by which the desired pressure of the air or other ymotive fluid may be hadso that the cushioning effect'may be varied in the different cylinders according to requirements. The independent valvesfor the cushioning cylinders enable the setter to admit or let off pressure from any cylinder as he may find necessary.V

In the cushioning 'means is included an adjustable stop to limit the tra-vel of the lever comprising part of the operating linkage. rlhe mounting for they cushioning means is so arranged that saidcushioning means may be readily placed on the knee of a` saw-mill carriage already in use. My

grab dog mechanism is also constructed to be readily placed on knees of carriages already in use. i

yof the knees,

The controls for handling the dog operat-V ing mechanism and the knee cushion mechanism of my invention are simple, compact, easily installed, and arranged so that they may be located conveniently to the setter "whoseduties require him' to occupy the control seat on the carriage.

I am aware that modifications may be re- -sorted to in carrying out the invention and while I have illustrated in the accompany-` ing drawings and, hereinafter described, a practical embodiment of the dog operating mechanism and the knee cushion mechanism, it is to be understood that other embodiments of the inventive principles-mayv be used.-

- In the accompanying drawings:

Figure 1 is a side elevation showing so much of a saw-mill carriage, one of its knees and grabv dogs as wiil illustrate the adaptation of my improvements thereof which are shown in said figure; Y

Figure 2 is a plan View, more or less diagrammatic, showing a saw-mill carriage having three knees equipped with my improvements, the controls for the dog operating mechanism and knee cushioning mechanisms being shown at different pointsfor the sake of clearness of illustration, whereas in practice they are arranged conveniently tothe luc" setterwho occupies the seat on the carriage; c

Figure 3 isa detail rear elevation of one showing my improvements applied thereto;

Figure 4 is a detail perspectiveof a part of the cushion mechanism;

Figure 5 is a detailv longitudinal section of theautomatic valve; f

Figure 6 is a detail perspective of the controls for the dog operating mechanism; and

Figure 7 is a detailview of a pair of the grab dogs and their slides.

- `The saw-mill carriage is designated gener-V ally as 1, and the knees appear at 2, said knees being slidably `mounted and, also, adjustable, in theusualmanner, by racks 3 of which one is shown, Figure 1. The said shaft i carries pinions of which oneis shown Any grab or boss dogs may be used in connection with my invention, a common form of dog appearing in Figures 1 and 7. These dogs 6 are arranged in pairs, pivoted together' at 7, and respectively pivoted to slides 8, 9, which are connected by operating connections 10, 11 to a. head 12 which is rocked by a rocker 13 mounted on a 'y shaft 14. Y

Pivotally mounted at 15 on the knee 2is a cylinder 16 in which is a 'piston 17 having av piston -rod18 pivoted at 19 to the rocker 13. Normally, the'piston 17 is at the upper orforivard end of the cylinder 16 atwhich point itis held by air pressure or any mol tive-fluid pressure employed,such pressure Y. AAs previously explained, this 'reducing valve enables pressure to be reduced when small logs, soft timber or valuablel timber is being handled or to be increased When hard wood is being dogged, thus enabling the dogging action to be economically and satisfactorily carried on at all times.v

I provi-de a novel automatic valve for controlling the supply of motive fluidV pressure to one side or the other of the piston 17, as shownin Figure 5. The valve chest 2O contains a slide valve 24 `which isadapted to put either port 25 or port 26 in communication with the cylinder 16 and to exhaust, through the exhaust port 27 the'pressure so that there v-Jill be no opposition to the movement of the piston when the pressure is changed from one yside to the other Vside thereof. rlie slide valve 24 is connected to a small Ypiston valve 23 anda larger piston valve 29 operating in cylinders 30, 31, the latter having a relief portr32. i there is constant motive fluid pressurefentering the valve chest from the pipe 21, this pressure causing the valve vto be maintained in the position shown in Figure 5, whereby the pressure has access to the cylinder 16 through the port 25, thus maintaining the piston 17 as shown in Figure 1 and the dogs 6 in their retracted or released position. lVhen, however, pressure is admitted through the pipe 33, under the control hereinafter described, the superior or greater superficial area of the piston valve 29 enables such pressure to shift the piston valves and the slide valve to the left, Figure 5, thus exhausting the air from cylinder 16 through port 25 and exhaust port 27 andr admitting the pressure from pipe 21 through port 26 to the opposite side of the piston 17 Whereupon the' piston 17 is instantly moved to the left hand endl of the cylinder 16. When this occurs, the rocker 13 shifts the slides 8 and 9 and causes thegrab dogs 6 to be operated for the purpose of dogging the log.

Each knee has mechanism such aspreviously described, there being control valves such as shown in Figure 5 for each cylinder 16. Each control valve has its own pipe 33. in each pipe 33 is a manually operablethree- Normally,

Waycontrolling valve 34 Whichenables the setter to admit or lexhaust the pressure to the different valves that controlthe cylinders 16 and Yto do so Whenever desired as Well as to exert an independent control over each controlling valve.

Thethreewvay valves 34 are connected to a 'header 35 which communicates With the motive fluid pressure tank 22. byva pipe. 36 in which is a master valve 37 and the pressure reducing valve 23. Themaster valve 37 is a three way valve and it is controlled either by a treadle 39, as shown in FiguresY 2 and 6, or in any other manner.

,The ypressure reducing valve 23 enables any desired adjustment to be had to determine the pressure which will be fed to the pipe 36 and pipes 33and 21 so that the desired regula-tionk of action may be obtained, as explained heretofore.

fNormally, as previously explained, the pressure entering the valve chest 20 through the pipe 21 shifts the valve pistons 28, 29, tothe right, Figure 5, because there is no opposing pressureV entering through pipes 33' as the master valve 37 is normally closed andisonly'opened on `manually operating it. `rl`herefore, thepistons 17 are all in ythe positionshown in Figure 1 which results in the grab dogs 6 being in released or retracted position as shown by dotted lines in Figure 1.

The valves-34 and 37Will -be arranged con. veniently for operation in front of the setter who occupies a seat on the carriage. He can open anyone or more of the valves 34 or close themas he may desire so that ihaving 'conditioned these valves 34 to cause the dogs 6 of any knee to be potentially set for operation, When he operates the valve 37, the pressure immediately flows from pipe 36 into the pipe or pipes 33 Whose valves 34 have been opened. The pressure which has access to the piston valve 29 at any knee, imme.

diately causes the slide valve 24 to be shifted to the left, Figure 5, to cut off the pressure the i from the left hand side of the piston 17 and to admit the pressure to the right hand side thereof whereupon the piston projects the dogs 6 for the purpose of clogging the log.

On turning any valve 34 to the exhaust position, the pressure is exhausted from pipe 33 and the piston 17 then returns to its normal position.. Thus, the setter has ab'- solute control at all times over the dogs of any knee independently of the dogs of every other knee, or, he may simultaneously operate the dogs of tivo or more knees to project or release them.

Vhen it is desired to release the dogs of all the knees simultaneously, this can be done by operating the valveV 37 to an exhausting position.' f f rEhe cushioning means is carried by a casting 40 which is also mounted on the pin 15 `the casting and at 43 to theknee.

Mounted in the bifurcated part 44 of the casting is the ear 45 of the cushion cylinder 46. Vithin the cylinder 46 is a piston 47 having a piston rod 48. Connected to an ear 49 which is attached to the rack 3, is a link.:50 which, in turn, is connected by a link 51 t-o the piston rod 48. rlhe link 51 is adapted tomove in a slot 52 in the casting 40 and its play. is limited by a screvv 53 carried by they casting 40. By adjusting the screw 53, the extent of play `of the piston 47 may be changed as desired. v

No 1mally, the piston 47 is held in the position shown in Figure 1, or in other position according to the adjustment of screw 53, by motive fiuid pressure admitted to the cylinder 46 through pipe 54. rlhere is a separate pipe 54 for each of the cylinders 46 and a separate cylinder 46, and links 50, 51 for each knee.. Each pipe 54 is provided with a vmanually operated three-Way valve 55 so that the pressure to each eylinder46 may be;

controlled independently of V the control of pressuieto each of the remaining cylinders 46. yThe pipes 54 are connected to a header 56 which, in turn, is connected to tank 22 by a pipe` 57. `A pressure reducing valve 58'is located in the pipe 57 so that the pressure which may be fed to the cylinders 46 can be regulated as desired. Obviously, the cushioning action needed will have to be lighter at times and at other times heavier, according to the size of the log. The pressure reduc-ing valve 5,8 enables the setter to change his pressure according to the log being handled. A master valve 59 is provided in the pipe 57.

The, controlling valves are located conveniently to ther setter so that he can change the pressure and open and close said valves at will.

While my cushioning mechanism tends to destroy the taper effect upon the log, such taper effect may be part-ly obtained after the log has been loaded on the carriage, because the setter can release the air from the cylinder 46 as the steam log turner places the-log in the desired position to be doggechinasmuch as thelog turner Will then push back a knee from which the pressure has been released so that theflog may be positioned in any desired manner.

After the log has been partly'savved and has one fiat side,the air is again applied to the-'cushion cylinder 46 topush the 10g to normal posit-ion. It Will be seen that with the use of thecylinders 46 and the pistons 47, the motive fluid pressure constitutes the sole means for holdingthe knees tothe Asawing line and as itis necessaryV for all of the knees to be'lined up, this can be accomplished by adjusting all of the set screws 53. i

Suitable relief valves 66 are provided fork the cylinders 46 desired amount. The valve 59 can be used tosimultaneously control the pressure in the cylinders 46, and they canbe independently controlled by the valves 55. Y

l/Vhat I claim is: s 1. ln a dog operating mechanism for saw mill carriages, the combination With motive ,to let'off pressure above any fluid pressure operated means for actuating and releasing the clogging means, automatic means controlling' the motive fluid pressure operated means to normally cause said motive fluid pressure operated means tovmaintain the clogging means inv released condiesV tion, and manually operable means for controlling the operation of said motive fluid pressure operatcdnieans through control of said automat-ic means, whereby the operator may cause the dogs to be actuated.

2. In a dogoperating mechanism for saw Will of the operator, whereby the clogging" means of each knee may be actuated or released asdesired independently of the actuation or release of the clogging means of the otherv knees. f

3. vIn a dog operating meehanismfor saw mill carriages, the combination With dogging means for Ythe different knees of the carriage, of independent motive fluid pressure operated means for actuating and re'- leasing the clogging means of the different knees, automatic means in each instance controlling the respective motive fluid pressure operated means aforesaid to normally maine tain the clogging means in released condition, independent manually operable means foi` independently controlling the operation of the respective motive fluid pressure operated meansthrough independent control of said automatic means at the will of the operator, whereby the clogging means-of each knee may be actuated or released as desired independent-ly of the actuation or release of the clogging means ofl the other knees, and a master controlling means adapted for operation at the will of the operator adapted to render the automatic means effective to vproject or retract the dogs of any knee whose independent manually operable controlling means has been set for control by said master controlling means, said independentcontrolling means being adapted for operation to restore the clogs of its knee to released position independently of the control exercised by the master controlling means.

4. In a. dog operating mechanism for saw mill carriages, the combination with clogging means for the different knees of the carriage, ofindependent motive fluid pressure operated means for actuating and releasing the clogging means of the different knees, independent manually operable means for independently controlling the operation of the respective motive fluid pressure operated means at the will of the operator, whereby the clogging means of each knee maybe actuated or released as desired independently of the actuation or release of the 'dogging means of the other knees, a master controlling means adapted for operation at the will of the operator, the control of the inde-pend ent manually operable means being subject to the control by said master controlling means, and motive fluid pressure reducing means which may be arranged to determine the degree of pressure exerted by the motive fluid which is under the control of the master controlling means.

5. In a dog operating mechanism for saw mill carriages, the combination with dogging means, of motive fluid pressure operated means for actuating and releasing said Y clogging means, an automatic motive fluid pressure operated valve controlling the admission, of motive fluid pressure to the aforesaid means, said valve'normally being actuated by the motive fluid pressure to admit the motive fluid pressure to the aforesaid means in a manner causing the clogging means to normally remain in released position, and manually operable means for controlling the admission ofl motive fiuid pressure to said valve at the. will of the oper@ ator for thev purpose of shifting the valve to operate the motive fluid pressure operated means to change its normal condition for the purpose of' actuating the clogging means.

6. In a dog operating mechanism for saw mill carriages, the combination with dogging means, of a piston and cylinder for actuating and releasing said clogging means, an automatic motive fluid pressure operated valve controlling the admission of motive fluid pressure to different parts of the cyl inder, said valve embodying pistons of different effective pressure areas, the piston of smaller area normally being actuated by the motive fluid pressure to admit the mo'- tive fluid pressure to the cylinder in a manner causing the release of the clogging means. and manually operable means for controlling theA admission of motive fluid pressure to the piston of greater eii'ective area of said valve at the will of the operator for the purposepof shifting the valve to admit the pressure to another part of' the cylinder to cause movement of the piston from its normal position for the purpose of actuating the clogging means.

In testimony whereof I aflix my signature.

JAMEs M. BROPHY. 

